Process of manufacturing acid-proof and waterproof black ink



duces precipitates.

Patented Dec. 10, 1929 J'INKIGHI moves, or SENDAI, airIYaeLxnis, APAN rnocnss or MANUFACTURING Acre-moor .imn-wnmnnrnoor BLACK INK NoDrawing. Application filed June 9,

black ink, and the object thereot is to obtain an ink which resists Water and Vvrltlng ink 110W generally in use s arm);-

This invention relates to .manutacture of ture handed down from several hundred years ago and consists of a solution of ferrous ianuate mixed with a coloring matter. Several materials are added thereto to increase its consistency, and its decomposition is pre- 10 vented by mixing an acid therewith. But such a mixture is not ideal asink, because a ferrous salt acting as a catalyzer of oxidation, changes the nature of the ingredients trom time to time While being used, andpro- At the same time the acidity increasing, even a metallic pen will be corroded. Moreover, on account of the changes of the nature ofthe ingredients, its blacking capacity decreases and the ink becomes unfit for use.

To remove these drawbacks, and manufacture ideal ink, the inventor thought it necessary to simplify the ingredients and to select such a compound which gives a colloidal solution. After a long experiment,he

has found that ammoniumsalt of tetraor hexanitro-sulphonic acid of di-naphthylenedioxide, is suited for this purpose. The starting material, di-naphthylene-dioxide so obtained by heatingin an autoclave amiX- ture of ,8-naphthol and cupric oxide or manganese peroxide, according to the following reaction.

as ink.

Solutions of the above derivatives in the form of annnonium salt are all of colloidal nature, and characters Written With such ink, if dried, are absolutely fast to Water and acid, having great resisting property against sulp r alkallra th. itr ra y and can b useeioiim last drop. Moreover rial n 36,020.

bleaching agents ,and moreover acquires an t ,property a certain treatment. inkis made or a simple ingredient,

changes ,itsnature While being used,

as it is neutral, it never corrodes the pen, and as 1t is not intermingled w th any other material, there 18 no fear of dregs collecting on h .Pe lso as the -ink gives .a colloidal solution it precipitate iian acid is added there o such precipitate may be filtered,

ivashedavith water and dried tobe formed nto solid nkelementwhich can be dissolved namn o n a aterto get a liquid ink. Inns sl d.

form it as yeryconvenient for transportation ,oi a "large, quantity.

follorvingare a few examples of manufac urin 'm ui Example I toglpart of di ilaphthylene-dioxide v6 parts ofa strongnitricacidt specific gravity crystals :VVash ,the, crystals yvith Water and dry Take l part of the. dried crystals nd .d

solve .them in 30 parts (ii. a strong heattl e solution to 1 70 180, C. and is kept ,that temperature for 73-4: hours, a and the s, changedinto dark violet. It thcliqnid is leftto cooland thrown into water, black ,precipitate ,talls down, which When filtt a dilute purple washed with Water, and dissolved in solution of ammonia, colloidal ink of black color is obtained.

c iente e 1 to ,1 part of .di naphthylene dioxide ,pa ts of a strong nitric acid (specific gr avrty 138) and; heatthe mixture {for about hears at a temperature of 110 (1., and

heated for Qlior, hours after adding .30 ,parts of strong. sulphuric acid ic acid (specific gravity 1.8), and n Example III Add to 1 part of di-naphthylene-dioxide 10 parts of a strong nitric acid (specificgravity 1.38) and shaking the fluid for half an hour, add thereto 2 parts of a strong-sulphuric acid. Then heat the liquid to 105 to 110 C. for four hours, and a hexa-nitro-derivative will be obtained in the shape of thin rhombio crystals of orange color. This is washed with Water and dried, and is treated as in Example II, and a colloidal ink of purple black color is obtained.

Emmpze IV Add to 1 part of di-naphthylene dioxide 10 parts of a strong nitric acid and 2 parts of Water, and after shaking the liquid for 2 hours, heat it'to 105110 C. for four hours;

and hexa-nitro derivative will be obtained in a form of needle crystals of orange color.

This is Washed with water and dried, and to 1 part of it, is added parts of a strong sulphuric acid. The mixture is then heat-ed to 160 C. for two hours, and then a black colored solution is obtained. This is left to cool and throw into water, and a black precipitate falls down. The precipitate is filtered and if it is dissolved in a suitable quantity of a dilute ammonia water, a colloidal ink of pure black color will be obtained.

Example V To 1 part of rhombic flakes of hexa-nitro derivative of di-naphthylene-dioxide add fluid of dark purple color. Distil the liquid about 20 parts of ammonia water (specific gravity, 0.956), and if the mixture is heated, it will gradually dissolve and become a and remove excess of ammonia,and acidulate the remaining liquid. Then a black precipitate will fall down.' The precipitate is dissolved in a suitable amount of water, and a colloidal ink of purple black color will be obtained.

Example VI precipitate formed by adding an acid to such ink, and to 1 part of it add 10 parts of a strong sulphuric'aeid. Heat the mixture to 90 C. for 2 hours, and a solution of dark violet color will be obtained. Cool the solu tion, throw it in Water, separate the precipitate by filtration. and by dissolving the same in a suitable amount of ammonia water, an ink of dark purple color will be obtained.

Ewample V] I Separate by filtration the black precipitate obtained in Examples I-VI, and wash and dryit, and the various kinds of ink in solid form will be obtained in solid form (ink element). These are all easily soluble in ammonia water, and thus a writing ink can be obtained.

From the foregoing it will be observed that the process comprises two essential steps, namely, the treatment of a solution of tetraor hexa-nitro-derivative in sulphuric acid so as to produce from said solution a precipitate, and the dissolution of said precipitate in ammonia to produce a colloidal ink.

Claims- 1. The process of manufacturing ink, which consists in dissolving a tetra-nitroderivative of di-naphthylene-di-oxide in sulphuric acid, treating the solution to produce a precipitate therefrom, and dissolving said precipitate in ammonia.

2. The process of manufacturing ink, which consists in adding nitric acid to dinaphthylene-di-oxide and heating the mixture to produce a tetra-nitro-derivative in the form of crystals, dissolving said crystals in sulphuric acid, treating the solution to produce a precipitate, and dissolving said precipitate in ammonia.

The process herein described, which consists in forming a tetra-nitro-sulphonic acid of di-naphthylene-di-oxide, treating said product to produce a precipitate, and dissolving said precipitate in ammonia.

4:. The process herein described, which consists in treating di-naphthylene-di-oxide to produce a tetra-nitro-derivative, dissolving said derivative in sulphuric acid, treating the solution to produce a precipitate therefrom, and dissolving said precipitate in ammonia.

In testimony whereof I have aflixed my signature.

JINKICHI INOUYE. 

